/*
 * Copyright 2012 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */
package io.netty.testsuite.transport.socket;

import io.netty.bootstrap.Bootstrap;
import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelHandler.Sharable;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.ssl.OpenSsl;
import io.netty.handler.ssl.OpenSslContext;
import io.netty.handler.ssl.SslContext;
import io.netty.handler.ssl.SslContextBuilder;
import io.netty.handler.ssl.SslHandler;
import io.netty.handler.ssl.SslHandshakeCompletionEvent;
import io.netty.handler.ssl.SslProvider;
import io.netty.handler.ssl.util.SelfSignedCertificate;
import io.netty.handler.stream.ChunkedWriteHandler;
import io.netty.testsuite.util.TestUtils;
import io.netty.util.concurrent.Future;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;
import org.junit.AfterClass;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;

import java.io.File;
import java.io.IOException;
import java.security.cert.CertificateException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Random;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicReference;
import javax.net.ssl.SSLEngine;

import static org.hamcrest.Matchers.anyOf;
import static org.hamcrest.Matchers.is;
import static org.hamcrest.Matchers.not;
import static org.hamcrest.Matchers.sameInstance;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertSame;
import static org.junit.Assert.assertThat;

@RunWith(Parameterized.class)
public class SocketSslEchoTest extends AbstractSocketTest
{

    private static final InternalLogger logger = InternalLoggerFactory
            .getInstance(SocketSslEchoTest.class);

    private static final int FIRST_MESSAGE_SIZE = 16384;

    private static final Random random = new Random();

    private static final File CERT_FILE;

    private static final File KEY_FILE;

    static final byte[] data = new byte[1048576];

    static
    {
        random.nextBytes(data);

        SelfSignedCertificate ssc;
        try
        {
            ssc = new SelfSignedCertificate();
        }
        catch (CertificateException e)
        {
            throw new Error(e);
        }
        CERT_FILE = ssc.certificate();
        KEY_FILE = ssc.privateKey();
    }

    protected enum RenegotiationType {
        NONE, // no renegotiation
        CLIENT_INITIATED, // renegotiation from client
        SERVER_INITIATED, // renegotiation from server
    }

    protected static class Renegotiation
    {
        static final Renegotiation NONE = new Renegotiation(
                RenegotiationType.NONE, null);

        final RenegotiationType type;

        final String cipherSuite;

        Renegotiation(RenegotiationType type, String cipherSuite)
        {
            this.type = type;
            this.cipherSuite = cipherSuite;
        }

        @Override
        public String toString()
        {
            if (type == RenegotiationType.NONE)
            {
                return "NONE";
            }

            return type + "(" + cipherSuite + ')';
        }
    }

    @Parameters(name = "{index}: serverEngine = {0}, clientEngine = {1}, renegotiation = {2}, "
            + "serverUsesDelegatedTaskExecutor = {3}, clientUsesDelegatedTaskExecutor = {4}, "
            + "autoRead = {5}, useChunkedWriteHandler = {6}, useCompositeByteBuf = {7}")
    public static Collection<Object[]> data() throws Exception
    {
        List<SslContext> serverContexts = new ArrayList<SslContext>();
        serverContexts.add(SslContextBuilder.forServer(CERT_FILE, KEY_FILE)
                .sslProvider(SslProvider.JDK).build());

        List<SslContext> clientContexts = new ArrayList<SslContext>();
        clientContexts.add(SslContextBuilder.forClient()
                .sslProvider(SslProvider.JDK).trustManager(CERT_FILE).build());

        boolean hasOpenSsl = OpenSsl.isAvailable();
        if (hasOpenSsl)
        {
            serverContexts.add(SslContextBuilder.forServer(CERT_FILE, KEY_FILE)
                    .sslProvider(SslProvider.OPENSSL).build());
            clientContexts.add(SslContextBuilder.forClient()
                    .sslProvider(SslProvider.OPENSSL).trustManager(CERT_FILE)
                    .build());
        }
        else
        {
            logger.warn("OpenSSL is unavailable and thus will not be tested.",
                    OpenSsl.unavailabilityCause());
        }

        List<Object[]> params = new ArrayList<Object[]>();
        for (SslContext sc : serverContexts)
        {
            for (SslContext cc : clientContexts)
            {
                for (RenegotiationType rt : RenegotiationType.values())
                {
                    if (rt != RenegotiationType.NONE
                            && (sc instanceof OpenSslContext
                                    || cc instanceof OpenSslContext))
                    {
                        // TODO: OpenSslEngine does not support renegotiation
                        // yet.
                        continue;
                    }

                    final Renegotiation r;
                    switch (rt)
                    {
                        case NONE:
                            r = Renegotiation.NONE;
                            break;
                        case SERVER_INITIATED:
                            r = new Renegotiation(rt, sc.cipherSuites()
                                    .get(sc.cipherSuites().size() - 1));
                            break;
                        case CLIENT_INITIATED:
                            r = new Renegotiation(rt, cc.cipherSuites()
                                    .get(cc.cipherSuites().size() - 1));
                            break;
                        default:
                            throw new Error();
                    }

                    for (int i = 0; i < 32; i++)
                    {
                        params.add(new Object[]
                        { sc, cc, r, (i & 16) != 0, (i & 8) != 0, (i & 4) != 0,
                                (i & 2) != 0, (i & 1) != 0 });
                    }
                }
            }
        }

        return params;
    }

    private final SslContext serverCtx;

    private final SslContext clientCtx;

    private final Renegotiation renegotiation;

    private final boolean serverUsesDelegatedTaskExecutor;

    private final boolean clientUsesDelegatedTaskExecutor;

    private final boolean autoRead;

    private final boolean useChunkedWriteHandler;

    private final boolean useCompositeByteBuf;

    private final AtomicReference<Throwable> clientException = new AtomicReference<Throwable>();

    private final AtomicReference<Throwable> serverException = new AtomicReference<Throwable>();

    private final AtomicInteger clientSendCounter = new AtomicInteger();

    private final AtomicInteger clientRecvCounter = new AtomicInteger();

    private final AtomicInteger serverRecvCounter = new AtomicInteger();

    private final AtomicInteger clientNegoCounter = new AtomicInteger();

    private final AtomicInteger serverNegoCounter = new AtomicInteger();

    private volatile Channel clientChannel;

    private volatile Channel serverChannel;

    private volatile SslHandler clientSslHandler;

    private volatile SslHandler serverSslHandler;

    private final EchoClientHandler clientHandler = new EchoClientHandler(
            clientRecvCounter, clientNegoCounter, clientException);

    private final EchoServerHandler serverHandler = new EchoServerHandler(
            serverRecvCounter, serverNegoCounter, serverException);

    public SocketSslEchoTest(SslContext serverCtx, SslContext clientCtx,
            Renegotiation renegotiation,
            boolean serverUsesDelegatedTaskExecutor,
            boolean clientUsesDelegatedTaskExecutor, boolean autoRead,
            boolean useChunkedWriteHandler, boolean useCompositeByteBuf)
    {
        this.serverCtx = serverCtx;
        this.clientCtx = clientCtx;
        this.serverUsesDelegatedTaskExecutor = serverUsesDelegatedTaskExecutor;
        this.clientUsesDelegatedTaskExecutor = clientUsesDelegatedTaskExecutor;
        this.renegotiation = renegotiation;
        this.autoRead = autoRead;
        this.useChunkedWriteHandler = useChunkedWriteHandler;
        this.useCompositeByteBuf = useCompositeByteBuf;
    }

    @Test(timeout = 30000)
    public void testSslEcho() throws Throwable
    {
        run();
    }

    @AfterClass
    public static void compressHeapDumps() throws Exception
    {
        TestUtils.compressHeapDumps();
    }

    public void testSslEcho(ServerBootstrap sb, Bootstrap cb) throws Throwable
    {
        final ExecutorService delegatedTaskExecutor = Executors
                .newCachedThreadPool();
        reset();

        sb.childOption(ChannelOption.AUTO_READ, autoRead);
        cb.option(ChannelOption.AUTO_READ, autoRead);

        sb.childHandler(new ChannelInitializer<Channel>()
        {
            @Override
            @SuppressWarnings("deprecation")
            public void initChannel(Channel sch) throws Exception
            {
                serverChannel = sch;

                if (serverUsesDelegatedTaskExecutor)
                {
                    SSLEngine sse = serverCtx.newEngine(sch.alloc());
                    serverSslHandler = new SslHandler(sse,
                            delegatedTaskExecutor);
                }
                else
                {
                    serverSslHandler = serverCtx.newHandler(sch.alloc());
                }

                sch.pipeline().addLast("ssl", serverSslHandler);
                if (useChunkedWriteHandler)
                {
                    sch.pipeline().addLast(new ChunkedWriteHandler());
                }
                sch.pipeline().addLast("handler", serverHandler);
            }
        });

        cb.handler(new ChannelInitializer<Channel>()
        {
            @Override
            @SuppressWarnings("deprecation")
            public void initChannel(Channel sch) throws Exception
            {
                clientChannel = sch;

                if (clientUsesDelegatedTaskExecutor)
                {
                    SSLEngine cse = clientCtx.newEngine(sch.alloc());
                    clientSslHandler = new SslHandler(cse,
                            delegatedTaskExecutor);
                }
                else
                {
                    clientSslHandler = clientCtx.newHandler(sch.alloc());
                }

                sch.pipeline().addLast("ssl", clientSslHandler);
                if (useChunkedWriteHandler)
                {
                    sch.pipeline().addLast(new ChunkedWriteHandler());
                }
                sch.pipeline().addLast("handler", clientHandler);
            }
        });

        final Channel sc = sb.bind().sync().channel();
        cb.connect().sync();

        final Future<Channel> clientHandshakeFuture = clientSslHandler
                .handshakeFuture();

        clientChannel.writeAndFlush(
                Unpooled.wrappedBuffer(data, 0, FIRST_MESSAGE_SIZE));
        clientSendCounter.set(FIRST_MESSAGE_SIZE);
        clientHandshakeFuture.sync();

        boolean needsRenegotiation = renegotiation.type == RenegotiationType.CLIENT_INITIATED;
        Future<Channel> renegoFuture = null;
        while (clientSendCounter.get() < data.length)
        {
            int clientSendCounterVal = clientSendCounter.get();
            int length = Math.min(random.nextInt(1024 * 64),
                    data.length - clientSendCounterVal);
            ByteBuf buf = Unpooled.wrappedBuffer(data, clientSendCounterVal,
                    length);
            if (useCompositeByteBuf)
            {
                buf = Unpooled.compositeBuffer().addComponent(true, buf);
            }

            ChannelFuture future = clientChannel.writeAndFlush(buf);
            clientSendCounter.set(clientSendCounterVal += length);
            future.sync();

            if (needsRenegotiation && clientSendCounterVal >= data.length / 2)
            {
                needsRenegotiation = false;
                clientSslHandler.engine().setEnabledCipherSuites(new String[]
                { renegotiation.cipherSuite });
                renegoFuture = clientSslHandler.renegotiate();
                logStats("CLIENT RENEGOTIATES");
                assertThat(renegoFuture,
                        is(not(sameInstance(clientHandshakeFuture))));
            }
        }

        // Ensure all data has been exchanged.
        while (clientRecvCounter.get() < data.length)
        {
            if (serverException.get() != null)
            {
                break;
            }
            if (serverException.get() != null)
            {
                break;
            }

            try
            {
                Thread.sleep(50);
            }
            catch (InterruptedException e)
            {
                // Ignore.
            }
        }

        while (serverRecvCounter.get() < data.length)
        {
            if (serverException.get() != null)
            {
                break;
            }
            if (clientException.get() != null)
            {
                break;
            }

            try
            {
                Thread.sleep(50);
            }
            catch (InterruptedException e)
            {
                // Ignore.
            }
        }

        // Wait until renegotiation is done.
        if (renegoFuture != null)
        {
            renegoFuture.sync();
        }
        if (serverHandler.renegoFuture != null)
        {
            serverHandler.renegoFuture.sync();
        }

        serverChannel.close().awaitUninterruptibly();
        clientChannel.close().awaitUninterruptibly();
        sc.close().awaitUninterruptibly();
        delegatedTaskExecutor.shutdown();

        if (serverException.get() != null
                && !(serverException.get() instanceof IOException))
        {
            throw serverException.get();
        }
        if (clientException.get() != null
                && !(clientException.get() instanceof IOException))
        {
            throw clientException.get();
        }
        if (serverException.get() != null)
        {
            throw serverException.get();
        }
        if (clientException.get() != null)
        {
            throw clientException.get();
        }

        // When renegotiation is done, at least the initiating side should be
        // notified.
        try
        {
            switch (renegotiation.type)
            {
                case SERVER_INITIATED:
                    assertThat(
                            serverSslHandler.engine().getSession()
                                    .getCipherSuite(),
                            is(renegotiation.cipherSuite));
                    assertThat(serverNegoCounter.get(), is(2));
                    assertThat(clientNegoCounter.get(), anyOf(is(1), is(2)));
                    break;
                case CLIENT_INITIATED:
                    assertThat(serverNegoCounter.get(), anyOf(is(1), is(2)));
                    assertThat(
                            clientSslHandler.engine().getSession()
                                    .getCipherSuite(),
                            is(renegotiation.cipherSuite));
                    assertThat(clientNegoCounter.get(), is(2));
                    break;
                case NONE:
                    assertThat(serverNegoCounter.get(), is(1));
                    assertThat(clientNegoCounter.get(), is(1));
            }
        }
        finally
        {
            logStats("STATS");
        }
    }

    private void reset()
    {
        clientException.set(null);
        serverException.set(null);

        clientSendCounter.set(0);
        clientRecvCounter.set(0);
        serverRecvCounter.set(0);

        clientNegoCounter.set(0);
        serverNegoCounter.set(0);

        clientChannel = null;
        serverChannel = null;

        clientSslHandler = null;
        serverSslHandler = null;
    }

    void logStats(String message)
    {
        logger.debug(
                "{}:\n" + "\tclient { sent: {}, rcvd: {}, nego: {}, cipher: {} },\n"
                        + "\tserver { rcvd: {}, nego: {}, cipher: {} }",
                message, clientSendCounter, clientRecvCounter,
                clientNegoCounter,
                clientSslHandler.engine().getSession().getCipherSuite(),
                serverRecvCounter, serverNegoCounter,
                serverSslHandler.engine().getSession().getCipherSuite());
    }

    @Sharable
    private abstract class EchoHandler
            extends SimpleChannelInboundHandler<ByteBuf>
    {

        protected final AtomicInteger recvCounter;

        protected final AtomicInteger negoCounter;

        protected final AtomicReference<Throwable> exception;

        EchoHandler(AtomicInteger recvCounter, AtomicInteger negoCounter,
                AtomicReference<Throwable> exception)
        {

            this.recvCounter = recvCounter;
            this.negoCounter = negoCounter;
            this.exception = exception;
        }

        @Override
        public void channelActive(ChannelHandlerContext ctx) throws Exception
        {
            if (!autoRead)
            {
                ctx.read();
            }
        }

        @Override
        public final void channelReadComplete(ChannelHandlerContext ctx)
                throws Exception
        {
            try
            {
                ctx.flush();
            }
            finally
            {
                if (!autoRead)
                {
                    ctx.read();
                }
            }
        }

        @Override
        public final void userEventTriggered(ChannelHandlerContext ctx,
                Object evt) throws Exception
        {
            if (evt instanceof SslHandshakeCompletionEvent)
            {
                SslHandshakeCompletionEvent handshakeEvt = (SslHandshakeCompletionEvent) evt;
                if (handshakeEvt.cause() != null)
                {
                    logger.warn("Handshake failed:", handshakeEvt.cause());
                }
                assertSame(SslHandshakeCompletionEvent.SUCCESS, evt);
                negoCounter.incrementAndGet();
                logStats("HANDSHAKEN");
            }
        }

        @Override
        public final void exceptionCaught(ChannelHandlerContext ctx,
                Throwable cause) throws Exception
        {
            if (logger.isWarnEnabled())
            {
                logger.warn("Unexpected exception from the client side:",
                        cause);
            }

            exception.compareAndSet(null, cause);
            ctx.close();
        }
    }

    private class EchoClientHandler extends EchoHandler
    {

        EchoClientHandler(AtomicInteger recvCounter, AtomicInteger negoCounter,
                AtomicReference<Throwable> exception)
        {

            super(recvCounter, negoCounter, exception);
        }

        @Override
        public void channelRead0(ChannelHandlerContext ctx, ByteBuf in)
                throws Exception
        {
            byte[] actual = new byte[in.readableBytes()];
            in.readBytes(actual);

            int lastIdx = recvCounter.get();
            for (int i = 0; i < actual.length; i++)
            {
                assertEquals(data[i + lastIdx], actual[i]);
            }

            recvCounter.addAndGet(actual.length);
        }
    }

    private class EchoServerHandler extends EchoHandler
    {
        volatile Future<Channel> renegoFuture;

        EchoServerHandler(AtomicInteger recvCounter, AtomicInteger negoCounter,
                AtomicReference<Throwable> exception)
        {

            super(recvCounter, negoCounter, exception);
        }

        @Override
        public final void channelRegistered(ChannelHandlerContext ctx)
                throws Exception
        {
            renegoFuture = null;
        }

        @Override
        public void channelRead0(ChannelHandlerContext ctx, ByteBuf in)
                throws Exception
        {
            byte[] actual = new byte[in.readableBytes()];
            in.readBytes(actual);

            int lastIdx = recvCounter.get();
            for (int i = 0; i < actual.length; i++)
            {
                assertEquals(data[i + lastIdx], actual[i]);
            }

            ByteBuf buf = Unpooled.wrappedBuffer(actual);
            if (useCompositeByteBuf)
            {
                buf = Unpooled.compositeBuffer().addComponent(true, buf);
            }
            ctx.write(buf);

            recvCounter.addAndGet(actual.length);

            // Perform server-initiated renegotiation if necessary.
            if (renegotiation.type == RenegotiationType.SERVER_INITIATED
                    && recvCounter.get() > data.length / 2
                    && renegoFuture == null)
            {

                SslHandler sslHandler = ctx.pipeline().get(SslHandler.class);

                Future<Channel> hf = sslHandler.handshakeFuture();
                assertThat(hf.isDone(), is(true));

                sslHandler.engine().setEnabledCipherSuites(new String[]
                { renegotiation.cipherSuite });
                logStats("SERVER RENEGOTIATES");
                renegoFuture = sslHandler.renegotiate();
                assertThat(renegoFuture, is(not(sameInstance(hf))));
                assertThat(renegoFuture,
                        is(sameInstance(sslHandler.handshakeFuture())));
                assertThat(renegoFuture.isDone(), is(false));
            }
        }
    }
}
